SECOND LINE DRUGS-Contd...
5.Penicillamine:-
The mechanism of its anti-rheumatic action is due to its ability to alter the immune response of the body. Penicillamine used to treat refractory rheumatoid arthritis. Its use is now very limited with more modern medication with fewer side effects.
Chemically penicillamine is a breakdown product of penicillin.
It delays the onset of joint erosions in RA.
Absorption
Penicillamine should be given in an empty stomach as food may interfere with its potency and block its absorption. As penicillamine is a chelating agent it may chelate all polyvalent ions present in the food such as calcium, magnesium, copper, iron, and zinc. These chelates are not absorbed by the intestine.
Dosage
The initial dosage is 125 - 250 mg once daily. Then the dosage is doubled after 3 months. After the next 3 months again the dose is doubled to a maximum of 750 mg daily until to get a required therapeutic effect. Very rarely the daily dosage can be maximized to 1000 to 1500mg under strict supervision. The basic dosing moto for this drug is to go low-go slow.
Side Effects
1.Reversible side effects such as rash, fever, blood urine, proteinuria, dysgeusia(distortion of the taste sense) and aphthous ulcers(mouth ulcers)
2.Vascular complications like leukopenia, thrombocytopenia and aplastic anemia
3. Systemic Lupus Erythematosus, Good Pasteur's Syndrome, and pemphigus have occurred. All these are autoimmune diseases in which the body's own immune system wrongly attacks its own skin, kidneys, and lungs.
6.Azathioprine
It is an autoimmune suppressor. It is a purine analog. It is used as a last attempt if other agents are not responded (refractory RA)
The dosage is 50 to 100 mg twice daily (1mg/kg). After 6 to 8 weeks the dose can be increased by ever 4 weeks by 0.5mg/kg.to a maximum of 2.5mg/kg.daily.
The dosage should be reduced in patients with renal dysfunctions.
Side Effects
1.Gastrointestinal effects such as nausea, vomiting, stomach pain,
2.Liver damage
3.Bone marrow suppression
4.Lymphoma
7.Cyclophosphamide
Similar to other immunosuppressive agents this antineoplastic agent can also be used in the treatment of refractory RA. But the use is limited because of its severe toxicity when compared with other immunosuppressive agents.
The initial dose is 1.5 to 3 mg/kg of the body weight.
Side Effects
1.Bone marrow depression
2.hemorrhagic cystitis
3.steriliy
4.Alopecia
5.Bladder cancer.
Other similar drugs are chlorambucil, cyclosporine. These are also immunosuppressive agents used in neoplastic treatments with a high toxic profile. Used to treat refractory RA.
Minocycline an antibiotic that can affect the Mycoplasma organism, the organism which causes RA.
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